Anchor chain rode

[billyfish]

What do we think the minimum amount of chain to rope rode is required for say a 30 foot 5 ton boat in 6 mts of water. I have 35 mts of 8mm chain with 10mts of rode with a 10kg hook. I was thinking of going down to say 10mts of chain or even less.

 

[BabaYaga]

What do we think the minimum amount of chain to rope rode is required for say a 30 foot 5 ton boat in 6 mts of water. I have 35 mts of 8mm chain with 10mts of rode with a 10kg hook. I was thinking of going down to say 10mts of chain or even less.

On a boat just slightly smaller (29 foot 3.6 ton) I have settled on 20 metres of 8mm chain, followed by 14mm octoplait nylon, 45 metres of length. I think it gives a good balance, as there will rarely be any rope on the sea bed. Most times I will have all the chain out plus anything from a few metres of rope up to several tens of metres, depending on conditions. Still lifting the chain plus anchor from maximum anchoring depth (say 15 metres) is manageable without a windlass.

 

[michael_w]

I work on 3 x depth of water. Maybe add a bit on for luck, so 2Om. Depends slightly on anchor and conditions. eg. a Bruce is an excellent short scope anchor and can be snugged up quite tight in good holding ie sand or sticky mud. Dunno about the fashionable anchors rocna et al.

No doubt someone will be along to say 'Unless you veer 60 meters with a 50 Kg fiisherman anchor you will die'

 

[Neeves]

There is no definitive anchor.

Most modern anchors,Knox, Spade Excel, Odin will work at short scope, 3:1, you might need a bit of patience initially to get them to engage but once the toe starts to bury they will set securely. All bets are off if its blowing 45 knots.

Don't use dyneema - it floats.

The idea is to have the rope off the seabed - but once a year and a sand seabed you would have no issues.

If you don't know or have any worries about the seabed you really don't want the rope abrading on rock with the rode taut. Similarly you don't want to be using textile in mud (the ideal seabed for a Bruce - it will be a devil to wash off.

If you are retrieving by hand and have 8mm chain I'd dump the 8mm and add a longer length of 6mm. You simply don't need the strength of 8mm with a 5t boat and certainly don't need the catenary effect with a decent length of nylon in use.

Jonathan

 

[Refueler]

What do we think the minimum amount of chain to rope rode is required for say a 30 foot 5 ton boat in 6 mts of water. I have 35 mts of 8mm chain with 10mts of rode with a 10kg hook. I was thinking of going down to say 10mts of chain or even less.

Why are you changing ? is it due to the weight carried fwd ? Or effort needed to retrieve on board ?

I'm a Ships guy .. so chain is my goto ...

But in keeping with the yottie role ... in your position .. I would stick with present setup .. or if you really want to change .. I would have at least 20m of chain and then similar or longer of rope rode.

At end of day ... whatever is claimed ... Catenary is IMPORTANT .... not only in terms of snatch - but also the direction of pull on the anchor of whatever design you choose.

BUT as a short time stop .. ie an hour or so fishing or grab a lunch ... I use one of those reels with braided tape ... with a short 1m length of chain ... I would never leave the boat while its used .. but its handy for the short stop.
I'll be honest - I'm not exactly too comfortable leaving a boat on its hook anyway .. so tend to lay out more than 3:1 ...

 

[Stemar]

Jazzcat (8m cat) has about 10m of chain, plus lots of rope. My last boat (24ft) had 17m, plus rope, but the chain was a lot smaller. Both work just fine, though I liked the longer length of chain better. Even so, as I get older, 17m of 8mm chain plus a 10kg anchor is just too heavy.

If weight is the issue, I'd consider going for a smaller chain, in a higher grade if necessary for strength, as part of a mixed rode.

 

[boomerangben]

I’m not sure I’d be that concerned about rope being on the seabed. Since the weight of submerged nylon is quite small, it won’t take much wind/tide to lift the whole rope part of the rode off the sea bed. I don’t remember ever having mud on the rope with 5m of chain. Of course if there are protruding rocks, you might want more chain. But with 6m of water and say a 4:1, 24m of rode, 18m of chain would mean the rope would never get to the seabed anyway. I’d be happy with 15m to be honest

 

[samfieldhouse]

On a boat just slightly smaller (29 foot 3.6 ton) I have settled on 20 metres of 8mm chain, followed by 14mm octoplait nylon, 45 metres of length. I think it gives a good balance, as there will rarely be any rope on the sea bed. Most times I will have all the chain out plus anything from a few metres of rope up to several tens of metres, depending on conditions. Still lifting the chain plus anchor from maximum anchoring depth (say 15 metres) is manageable without a windlass.

This is exactly what I have on my 28ft-er.

 

[thinwater]

What do we think the minimum amount of chain to rope rode is required for say a 30 foot 5 ton boat in 6 mts of water. I have 35 mts of 8mm chain with 10mts of rode with a 10kg hook. I was thinking of going down to say 10mts of chain or even less.

More information.

• Windlass or pull by hand?
• Any rocks down there to snag/cut the rope?
• Anchors do not work based on weight alone or we could just use a rock. We should not think of anchors by-the-pound. What kind? CQR? Viking? No-name?

And 8mm chain is too big. 6 mm G43 is enough. That will save a good bit of weight.

 

[billyfish]

The reason I'm pondering this is my boat is Scandinavian and the anchor chain is in a silly little bow locker that isn't big enough and all the weight is up forward high up. I have a manual windlass 8mm and the chain has a join half way along I might just go for one half as I have some octoplat and suck it and see. Tha anchor is actually to big for the boat 16kg but fits and was cheap. In the future I want to get a electric windlass and put a pipe to a locker below the waterline , it's possible but ......well you know.

 

[Refueler]

My 38ft'r is Swedish and has no provision at all for anchor fwd .. no locker, no roller, etc.

I know your 'pain'.

Its one of the reasons that the Ankorlina reels came about ... to at least give Skandy boats something to use if not bow moored to a pontoon !

 

[Stemar]

I have a manual windlass 8mm

If your current gypsy can't do it, you should be able to find one that will also work with the rope. Mine does. Even the splice goes through fine, though I do have to help it down the hawse hole.

I couldn't find the figures online quickly, but I believe that 6mm G79 chain will have a similar strength to 8mm "ordinary" chain, but with a big weight saving. (If I'm wrong, someone will be along PDQ to say so)

If you do go down that route, and the budget allows, a switch to an electric winch at the same time would make sense, as a new gypsy is a significant proportion of a new electric winch with the right gypsy, and your back will be EXTREMELY grateful

 

[MAURICE]

Ive owned my current boat about 18 years and travelled to many destinations abroad and anchored a lot. My recommendations would be get a heaver anchor perhaps next size up and lay min. 4x scope of Chain. Use rope to extend scope if needed but then always check the rope regularly when anchored.

 

[billyfish]

I usually go X5 if it's blowing

 

[Tranona]

My recommendations would be get a heaver anchor perhaps next size up

Why? His current anchor is already too big as is his chain. The objective is to reduce weight up high and forward. 6mm chain and a 10kg anchor will be more than adequate. Worth considering if he takes the plunge and goes for a new windlass, Otherwise not a lot of point in changing anything now.

 

[Neeves]

Billy could reduce the weight further by using a Viking 10 or Odin 40 at 8kg, both will outperform his current 10kg choice.

A beauty of 6mm chain is that it is so easy to retrieve by hand - its simply so light and does not demand an electric windlass as a 'back saver'. An electric windlass is nice, with 6mm, but nor essential. However if Billy is disadvantaged by age and has an overflowing wallet - then a windlass will be a godsend.

I also don't think it necessary to increase the strength of the 6mm by replacing G30 with either G40 or G70 x 6mm. If you are using G30 6mm and its going to be rough/windy you will be deploying the textile portion of the rode and it will offer all the snubbing you need and factorially reduce the tension in the rode.

Ive owned my current boat about 18 years and travelled to many destinations abroad and anchored a lot. My recommendations would be get a heaver anchor perhaps next size up and lay min. 4x scope of Chain. Use rope to extend scope if needed but then always check the rope regularly when anchored.

I'd like to see the quantitative data to support the idea that a 5t yacht needs an anchor bigger than 10kg. On our 7t x 38' x 22'6" beam cat, which we owned for 25 years, we used 8kg alloy anchors, Spade or Excel. No problems anchoring in Tasmania's SW coast facing The Southern Ocean.

We also used 6mm chain, but a G70 quality. I suspect we had greater windage than Billy's yacht. We did not have a mixed rode but separate snubbers, a bridle.

Jonathan

 

[Otter]

I found this thread really helpful, going through similar questions with a very similar boat. Particularly helpful was the absence of recommendations to go two sizes and lengths up on everything “just in case”.

 

[Roberto]

Particularly helpful was the absence of recommendations to go two sizes and lengths up on everything “just in case”.

Open another identical thread and you ll get them, or just wait here

 

[NormanS]

I found this thread really helpful, going through similar questions with a very similar boat. Particularly helpful was the absence of recommendations to go two sizes and lengths up on everything “just in case”.

It depends so much on the type of anchoring that you might be doing.

 

[Neeves]

Th religion of recommending an oversized anchor as a solution to all anchor woes has been thrashed to death and many members here have seen the light and the true path and have abandoned the idea.

Vyv Cox summarised the arguments against a bigger anchor here

Oversize anchors – necessary?

I and a number of others fully support Vyv's words and for those who are still closet believers, or are bored, I suggest you start a new thread and quantify your arguments. No need to ruin a perfectly sensible thread with unsubstantiated claims that 'bigger is better'

Jonathan